We know Emma Watson likes to make an impression when it comes to her red carpet outfits - but we never expected to see her go all punk rock on us.

The actress stunned in a floor-length backless black gown for the Noah premiere in New York on Wednesday night - and we saw a whole different side to her.

A rather Gothic side actually.

With her hair pinned back and showing off some very black nails, the star looked elegant beyond her years.

The 23-year-old recently told E! News she enjoys dressing up in edgy outfits and added: "I've just really embraced that side of my job, I guess, because you have to do these appearances and so you might as well make it fun."

And Emma admitted the new biblical epic has had a huge impact on the way she views the world.

She told the site: "You see the movie and you go, 'Wow, we are entrusted with this beautiful world,' and it kind of makes you want to make more of an effort and give back instead of take."

How did the Harry Potter star become so elegant? (Image: Larry Busacca/Getty Images for Paramount International)

She added: "I was so physically and emotionally exhausted by just the process of making the film.

"I just didn't leave my apartment for a few weeks, walked around in my pyjamas for a few days in a row. I just needed some time to sort of put myself back together a bit."

The brunette beauty wasn't the only one to leave a lasting impression.

On-screen couple Jennifer Connelly and Russell Crowe, who plays Emma's parents in the film, even gave each other a quick kiss on the cheek to celebrate.

A stunning looking Jennifer was the polar opposite of Harry Potter star Emma, and wore a bright yellow and green mini skirt, red leather boots and a black jacket.